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Charge and current electrostatics. Nonstationary sources of static fieldsThe problem of determination of the sources of an electrostatic field within the framework of Maxwellian electrodynamics has two forms of solution: stationary charges and nonstationary rotational current. For example, an external current which depends on the time $t$ according to a linear law and which flows along the surface of a toroidal solenoid creates in the external region a field identical to the field of an external charge dipole. From currents which increase as even powers of $t$ it is possible to construct magnetostatic multipoles, and from currents which increase as odd powers oft it is possible to construct electrostatic multipoles. Following Ya. B. Zel'dovich one can call toroidal current sources anapoles, and therefore a system of static fields produced by nonstationary toroidal currents can be classified as anapole static fields (anapole-statics). Such current sources have certain strange features. For example, when the current charges are placed in an electrostatic field they do not experience the usual Coulomb forces, but obtain from the field or give it an electromagnetic momentum, experiencing thereby a corresponding recoil. Taking into account this recoil re-establishes the equivalence of current and charge multipoles for any interactions.
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